External hard drive compatible with mac and Time Machine?

[AnonymousBird]

I think I need a new external hard drive to manage my system back ups. I have one which is donkeys years old and it's memory size isn't that great. On doing a bit of research, I gather that some don't work so well to back up a Mac (eg. www.amazon.co.uk/Samsung-Slimline-Portable-Hard-Drive/dp/B008PABFX8/ref=sr_1_2?ie=UTF8&qid=1394797452&sr=8-2&keywords=hard%20drive%20for%20mac%29&tag=mumsnet&ascsubtag=mnforum-21

Any recommendations please? 1TB is the size I am after. thanks.

[prism]

That review is very misleading. To use a hard drive with Time Machine you wouldn't want extra software getting in the way anyway- the first thing to do is to format it for your Mac and then just start using it. That Samsung drive would have worked perfectly well, as would any other, but if you don't format it as HFS+ in the first place you may run in to trouble. I suggest you just buy the cheapest you can find.

[AnonymousBird]

Thanks prism.

Can I just ask please, how does one "format for Mac"? My current WD just plugs in and goes, I don't recall having to set it at any point and it was used previously on a PC. Also, what is HFS+?

Appreciate you taking the time to reply.

[prism]

By "Format for Mac" I mean "format in the way that works best with a Mac". Macs can read all common formats, so it's not strictly necessary, but it is a good idea.

There are 3 main formatting schemes used for common or garden computers- FAT32, NTFS, and HFS. FAT32 and NTFS were invented by Microsoft for PCs, and HFS was invented by Apple for Macs. The oldest format is FAT32 (FAT stands for File Allocation Table, it's nothing to do with calories), but it's not good for large files, which is why NTFS was invented. But absolutely everything (PCs, Macs, pretty much all computers, tablets, phones, cameras) can read FAT32 drives, which is why when drives are pre-formatted it tends to be in the (old and inefficient) FAT32 scheme. It's the lowest common denominator amongst the different formats. Incidentally none of this is anything to do with the make of the drive- all hard drives are like pieces of blank paper until they are formatted, and can all be made to do the same different things when they are (with differences in speed and capacity).

When you buy a drive and connect it to your Mac it will either be unformatted, in which case you'll be invited to format it and Disk Utility will spring into life for you to do so, or it will already be formatted, which looks good as it saves you the trouble of doing it yourself, but is not so good in that you may have large files that you won't be able to put on it, but you won't discover that until later, and even then the error message won't tell you what the real problem is. HFS is a better formatting scheme than either of the ones for PCs, and has better indexing and error checking, so it's always best to format your drives that way, for use with your Mac.

So, having connected it for the first time, run Disk Utility, in Applications/Utilities, and erase the drive. You will have an option of formatting it as HFS+ (journaled) or FAT32, so choose HFS+. You will then be asked if you want to use it to back up with Time Machine. Say yes, and away you go.

The only downside to this is that PCs can't read HFS drives without the addition of extra software, so you won't be able to use that drive to share with a PC. But if it's your backup drive I suggest you leave it for just that purpose anyway, so this wouldn't matter.

Sorry about the long answer. If you're really interested I'll tell you the difference between HFS and HFS+, and the significance of journaling. But you definitely don't need to know that :-)